1. Field of the Invention
The present invention relates generally to forage blowers and more particularly is directed to an adjustment mechanism for disposing the forage blower in a plurality of vertical positions relative to the ground.
2. Description of the Prior Art
Forage blowers are used to elevate crop material, such as silage, grain and the like into silos, storage bins, etc. The crop material is brought in from the fields in wagons and dumped into a generally horizontal feed table or trough having an auger, rotor impeller or other conveyor means which feeds the material to a high speed vertical fan, commonly referred to as a "blower," that blows or throws the material upwardly through a discharge pipe to the top of a silo or other storage facility.
The vertical blower is usually driven from the power take-off of a tractor which turns the fan at 540 rpm, or as in some of the larger new models, at 1000 rpm. The high speed of the fan, in forcing the crop material upwardly through the discharge pipe, creates an extreme amount of vibration which causes the blower unit to move about or gyrate on the ground. In addition to the vibration caused by the vertical fan, some vibration is also generated by the feed means, especially those units having a horizontal rotor type impeller.
It is necessary to provide a stationary support for the blower unit and thus, it has been the customary practice, to rest the unit on the ground, using its weight and broad base as a stabilizing factor. Another means of stabilizing the blower is through the use of a jack stand in combination with a set of fixed wheels as illustrated in U.S. Pat. No. 3,466,095.
Usually forage blowers are considered mobile units, to be transported from one site location to another, and thus are provided with transport wheels. Generally, these transport wheels are removably mounted such that the blower unit can rest on the ground during operation. Other units are provided with a mobile transport frame of the type appearing in U.S. Pat. No. 2,757,811. And, still other units are provided with retractable wheels, movable between transport and non-transport modes as illustrated in U.S. Pat. Nos. 2,639,949; 2,695,816; and 2,698,770. In each case, blocking or shimming is usually required to level the unit on uneven ground. This is especially pertinent to those units that are required to be level for efficient operation.
In operation, the blower unit is positioned at the base of the silo and its discharge spout is connected to a vertically extending silo fill pipe so that forage material can be transferred to the top of the silo. This connection has always caused a problem, generally requiring a shifting or adjusting of the blower unit such that the discharge spout properly aligns with the fill pipe. Some units are provided with adjustable discharge spouts to facilitate this alignment problem; however, such structure brings added costs and expense to the units.
The prior art attempts known heretofore for transporting a forage blower which provides a stable and sturdy base for the unit during operation thereof and which facilitates connection of the discharge spout to the silo fill pipe are cumbersome, complicated in structure, costly, time consuming and inconvenient for the operator to use.